Answer: It's hard to give you directions in this format on how to build a cold frame. I'd suggest going to your local library and looking in some gardening books for diagrams and instructions. They can be as simple as nailing 2 x 6 lumber boards into a box and placing a window pane over it. You can start putting plants in the cold frame when the nights stay above about 25F. Start in April with, of course, cold tolerant plants such as broccoli, lettuce and cabbage. When you get closer to the last frost date in your area (about May 1) put out tomatoes, peppers and melons.
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